Manufacture of dyeing conversion products of azo-dyestuffs



Patented Mar. 22, 1932 p UNITED STATES PAT- E EDUARD HAeEnBAciLoAnL METTLER, AND ERICK wANnnR, oFnAsnn'swI TznnLAnn; .ASSIGNORS TO THE FIRMoF .T. n. GEIGY S. A., or Basing, swITzn trln sn MANUFACTURE on :IDYEZITINGT CONVERSION rnonoors on :nzo-nxnsrurrs No Dra ing- Application filed February 6,1929, Serial no.-s3s,02e,.ana in Germany-February 20,-,1925.

' as may be obvious to those versed in the art or may hereinafter appear, the present invention in one of its aspects consists in treating monoor polyazo dyestuffs. containing resorcin as a component, in the presence ofammonia with an oxidizing agent. Preferably air is employedas the oxidizing agent and heat is used during the reaction.

In this manner new dyeingproducts from azo-dyestuii's are formed which are still azodyestuffs, but of whichqthe exact constitution cannot be given. The technical efiect obtained thereby is very surprising. The original dyestufis which yield mostly yellow to red dyeings become brown to red-brown dyestutisthat are no longer capable of dyeing wool or silk or have only a little dyeing eiiect thereon, but which have taken an in creased dyeing power on leather. The dyes produced on leather are characterized by mainly brown to brown-violet tints of excellent fastness to light and alkaline fat liquor.

' According to a simpleform of the process the intial substances are treated with air in watery ammonia at increased temperature,

preferably at a temperature of at least 7 0 0. Such oxidation takes place even at ordinary.

temperature, but takes considerably longer. Also, other oxidizing agents, such for examplelas MnO can. housed, the essential feature being the presence of ammonia until}; the conversion has been concluded.

Thelfollowing example illustratesthe details of the improved process, the parts bej ing by weight A solution ,Of 24. pa -S of the mono azodyestuii from l-amino. benzene-i sulphonic acid and re'sorcin in lO'O-l50 parts of water 1s mixed ,,with30i.5 0 parts of ammonia of] 20% strength andlair is passed through at 7 080 C. whilst'stirring. The'initially pure] yellow orange solution soon becomes deep brown and the oxidation .is continued until thiejc'olorationj and strength" of the solution 1 do not chan'ge further,..which' is thej cas'e after a few hours. Thenacidification. with hydrochloric;acid lis effected, precipitation with {common salt, and filtering and drying; The ammonia salt solution may also be di rectly con'centrate'd: by; evaporation. I

The dyestu fii forms a d ark powder, soluble in water with a yellow brown coloration, and also soluble in concentrated sulphuric acid with'a yellow brown coloration. Whilst wool inanacid bath is hardly dyed thereby,

it produces on leather a dark yellow brown Table Azo combination 7 Azo body oxidized in presence of ammonia I Colora- Aqueous solu- Solution in I Aqueous solu- Solution in Constitution tion on tion of the dye HES O4 concen 333? 9 tion of the 112$ 04 concenleather acid trated NHi-salt trated Sulphanilic acid-)resorcin Yellow Yellow Yellow Brown Yellow-brown Yellow-brown Amino-oxy-benzene sulnho-carbox- Orange Yellow-orange Orange Brown Brown Brown ylic acid 2.1.4.6- resorcin. v p Naphthylamine-sulphonic acid 1.4 Yellow Brown-orange Red-brown Brown Brown Brown-violet resorcin. V Nanhthylamine disulphom'c acid Orange Yellow-orange Bed-orange Brown Yellow-brown Red-brown 2.3.6 rcsorcin. l

Sulphanilie Yellow Yellow Yellow-brown Yellow-brown Yellow-brown Brown ac resorcin c Aniline I V Amino-azo-benzene disulphonic acid Red ,Orange Blue 7 Brown Brown I Black )res'orcin. v I I C n a p h t h 01 disulphonic Red Red-orange Red-violet Violet Red-brown Violet acid 2.6.8. v I Benzidine resorcin.

' too What we claim is 1. A process for the production of dyeing products from azo-dyestutis, comprising subjecting a monoa'zo dyestuif formed by coupling a diazotized amino-sulfonic acid compound of the benzeneand naphthalene series with resorcin, tot-he action of an oxidizing agent in the presence of ammonia.

2. A process for the production of dyeing products from azo-dyestuffs, comprising subjecting a monoazo dyestuif formed by coupling a diazotized amino-sulfonic acid compound of the benzene and naphthalene series with resorcin, to the action of air passed.

therethrough in the presence of ammonia and preferably at a temperature of at least C.

3. As new articles of manufacture the dye ing products from azo-dyestuffs obtained by subjecting a monoazo dyestufi' formed by coupling a diazotized amino-sulfonic acid compound of the benzene and naphthalene serieswith resorcin, to the action of an oxidizing agent in the presence of ammonia. said dyeing products being dark powders. soluble in water with ayellow brown to a red brown coloration, soluble in sulphuric acid with a yellow-brown to black coloration, dyeing wool with difliculty in an acid bath. yielding on leather yellow brown to violet tints of great fastness to light and alkaline fat liquor.

In witness whereof we have hereunto signed our names this 25th day of January, 1929.

' EDUARD HAGENBACH.

CARL METTLER. ERICH WANNER. 

